Device for the removal and concentration of organic compounds from the atmosphere

Abstract

A device and method for removing, concentrating and analyzing airborne organic compounds. The device includes a nonporous membrane which contains a collection media. The liquid collection media typically includes a component which has a molecular weight that is too large to pass through transport corridors in the nonporous membrane and a component which has a molecular weight which is sufficiently small enough to pass through the transport corridors in the nonporous membrane and thereby forming a thin film on the exterior surface of the device. The collection media can consist of only components too large to pass through the membrane transport corridors. Organic contaminants are trapped in the thin film on the exterior surface of the device or the membrane and transported by concentration gradient diffusion forces into the bulk of the collection media within the nonporous membrane.

What is claimed is: 
     
       1. A method for collecting organic compounds from an atmosphere which comprises: providing an envelope made from a nonporous membrane which includes an inner space, an exterior surface, and membrane transport corridors that communicate between said inner space and said exterior surface;   providing an organic compound collection media within said inner space, said organic compound collection media comprises a first component having a molecular weight which is too large to pass through said membrane transport corridors and a second component having a molecular weight which is sufficiently small so as to pass through said membrane transport corridors;   allowing a portion of said second component to diffuse through said transport corridors and form a film on said exterior surface of said nonporous membrane envelope; and   exposing said envelope to an atmosphere which contains organic compounds, whereby during said exposure organic compounds are absorbed by said exterior film of said second component and transferred into said inner space of said envelope so as to be collected therein.   
     
     
       2. A method for collecting organic compounds from an atmosphere according to claim 1, wherein said atmosphere is within a confined space and said method further involves reducing the level of organic compounds within said confined space. 
     
     
       3. A method for collecting organic compounds from an atmosphere according to claim 2, wherein said confined space comprises a building. 
     
     
       4. A method for collecting organic compounds from an atmosphere according to claim 1, wherein organic compounds collected in said inner space of said envelope are subsequently analyzed. 
     
     
       5. A method for collecting organic compounds from an atmosphere according to claim 1, further comprising supporting said nonporous membrane on a microporous support membrane. 
     
     
       6. A method for collecting organic compounds from an atmosphere according to claim 1, wherein said nonporous membrane is made from a member selected from the group consisting of polyethylene, polyethylene terphthalate, polyimide, polypropylene, polyvinyl chloride, silicone, and mixtures thereof. 
     
     
       7. A method for collecting organic compounds from an atmosphere according to claim 1, wherein said collection media comprises a lipid, oil, silicone, hydrocarbon, or other lipid-like fluids. 
     
     
       8. A method for collecting organic compounds from an atmosphere according to claim 1, wherein said envelope has a surface-area-to-volume ratio of 6 cm 2  /g to 1000 cm 2  /g. 
     
     
       9. A method for collecting organic compounds from an atmosphere according to claim 1, wherein said collection media is reactive to organic compounds which are collected. 
     
     
       10. A device for collecting organic compounds from an atmosphere which comprises: an envelope made from a nonporous membrane which includes an inner space, an exterior surface, and membrane transport corridors which provide pathways for exchange between said inner space and said exterior surface; and   an organic compound collection media within said inner space, said organic compound collection media comprising a first component having a molecular weight which is too large to pass through said membrane transport corridors and a second component having a molecular weight which is sufficiently small so as to pass through said membrane transport corridors,   whereby a portion of said second component forms a film on said exterior surface of said nonporous membrane envelope and said first component is contained within said inner space of said envelope, and organic compounds are absorbed by said exterior film of said second component and are transported through said membrane transport corridors into said inner space of said envelope.   
     
     
       11. A device for collecting organic compounds from an atmosphere according to claim 10, wherein said nonporous membrane is made from a member selected from the group consisting of polyethylene, polypropylene, polyvinyl chloride, silicone, polyethylene terphthalate, polyimide, and mixtures thereof. 
     
     
       12. A device for collecting organic compounds from an atmosphere according to claim 10, wherein said nonporous membrane is laminated to a microporous support membrane. 
     
     
       13. A device for collecting organic compounds from an atmosphere according to claim 10, wherein said nonporous membrane has a thickness of 5 to 500 μm. 
     
     
       14. A device for collecting organic compounds from an atmosphere according to claim 10, wherein the surface-area-to-volume ratio of said device is 6 cm 2  /g to 1000 cm 2  /g collection media. 
     
     
       15. A device for collecting organic compounds from an atmosphere according to claim 10, wherein said collection media comprises a lipid or an oil. 
     
     
       16. A device for collecting organic compounds from an atmosphere according to claim 15, wherein said collection media comprises triolein. 
     
     
       17. A device for collecting organic compounds from an atmosphere according to claim 10, wherein said collection media is reactive to organic compounds which are collected. 
     
     
       18. A device for collecting organic compounds from an atmosphere according to claim 17, wherein said collection media is a member selected from the group consisting of organic acids, organic bases, silicone, hydrocarbons, and other lipid-like fluids, and mixtures thereof.